Navigational training aid



April' 17, 1945'. L v HORR 2,373,959

NAVIGATIONL TRAINING AID' Filed May 1o, 1944 2 sheets-sheet 1 BYl l ATTORNS -April 1'7, 1945. J. v. HORR 2,373,959

NAVIGATIONAL TRAINING ID -INVENTOR John, VHorr ai: g ATTORNZS Filed May 1o, 1944 Y 2l sheets-sheet 2- v Patened Apr. 17,l 1945 UNITED STATES,

NAVIGATIONAL TRAINING AID John V. Horr, North TarrytowmrN. Y., assignor'to Einson-Freeman Co., Inc., Long Island City, N. Y., a corporation of Delaware Application May 1o, 1944, serial No. 534,853

13 Claims.

My present invention relates generally to educationaldevices and has particular reference to a training aid intended to facilitate the teaching of certain phases of navigation.

A general object of the invention is to provide a device of simple and inexpensive structural character which lends itself readily to quantity manufacture at low cost, and which may be employed with striking effectiveness to teach those phases of the 'art of navigation Which relate to so-called relative bearing, target angles, and similar relationships. u A

Brieiiy stated, the present device. consists of a series of nterengaged relatively movable elements, preferably composed of pieces of flat sheet material, with pivotal interconnections which permit various adjustments to depict the relative positions of a vessel and target with respect to each other and to a compass direction. The term target as used herein .and in the parlance of navigation, Vespecially in connection with the phrase tarket angle, doesot necessarily allude to something which is aimed or iired at by means of a rearm, but includes Within its significance any object, such as another vessel, with respect to which certain positional relationships are to be observed or studied. Accordingly, in the preferred embodiment of the present invention, one of the elements depicts avessel while a second and relatively movable element is provided with a .target representation in the form or a second vessel. The various parts are of simple. structural shape and character, carrying certain markings and indicia which relate to the subject to be studied, and are preferably coupled with arelatively xed element which depicts a compass rose.

I4 achieve the foregoing general objects, and such otherobjects as mayhereinafter appear or be pointed out, in the manner illustratively exemplied in the accompanying drawings in which:

Figure 1 is a plan view of a training aid constructed in accordance with the present invention;

Figure 2 is an enlarged and slightly exaggerated cross-sectional view taken substantially'along the line 2--2 of Figure l;

Figure 3 is an exploded view of the principal elements entering into the construction; and

Figure 4 is a series of diagrams illustrating certain navigational relationships whose study is facilitated by means of the present device.

Preliminary reference to Figure 4 will facilitate an understanding ofthe nature and general mode of operation of thepresent device. Two

vessels A andi B are dlagrammatically shown in 55 ment I0 with respect to the backing I4, although 45 portions of the vessel.

three illustrative relationships, the relatively pointed end representing, in each case, the bow of the vessel, and the dot-and-dash line indicating the line of sight between them. The relative bearing of vessel B with respect to vessel A is the angle (in degrees) between the heading of vesselA and the line of sight between the vessels, measured in a clockwise direction. This relative bearing is, for example, approximately 10 90 in the iirst illustrative case, approximately 180 in the second case, and approximately 250 in the third case. The target angle of vessel B with respect to vessel A is the angle (in degrees) between the heading of vessel B and the l5 line of sight between the vessels, also measured in a clockwise direction. This ftarget angle is, for example, approximately 270 in the first illustrative casegapproximately 180 in the second case, and approximately 315 in the thirdcase.

0 Relative bearing and target angle are thus observed to be relative terms; i. e., the target angle of B with respect to A is the "relative bearing of A with respect to B, while the rela tive bearing of B with respect to A is the target 25 angle of A with'respect to B.

A full understanding of these terms, their signicance, the various values which they may assume under' different circumstances, and the relationships between them, can be acquired only :lo by considerable study. To Ifacilitate such study,

and to develop in the student afamiliarity with the subject, a device of the present character is highly effective, since it permits the student to 40 or elements of flat sheet material such as cardboard. An element I0 is contoured to depict a vessel in plan view outline. Markings on its upper surface, as indicated at Il and I2, .are preferably employedto accentuate the bow and stern A marking I3 in the form of a straight line extends between the bow and the stern to depict what is known as the lubber line which coincides with the fore and aft or keel line of the ship.

50 The element I0 is mounted flatwise upon a backing element I4 'so as to be rotatable in its own plane about a pivot axis I5 coinciding with a v midportion of the lubber line I3.` Thefdot-anddash line I6 indicates the rotatability of the eleit will be understood that the element I is freely rotatable in either direction through a complete are of 360.

Concentrically pivoted with respect to the element I0, and independently rotatable in a similar manner through a complete arc of 360 (as indicated by the dot-and-dash line I 1) is an element I8 in the form of a radial arm. At its end this arm is provided with a target representation. In the preferred embodiment of the invention, this target representation assumes the form of a third element I9 which is pivoted to the arm I8 at 2l) and which has a contour depicting a second vessel in plan view. The elementr I9v is freely rotatable in either direction through a complete are of 360 with respect to the arm I8 on which it is mounted.

The manufacture and assembly of the parts may be conveniently achieved in .the manner shown most clearly in Figure 3. The element IU is provided 'with a central circular aperture t9 and the element I is provided with an enlarged innerportiondefining a similar circular aperture 29. Mounted on the backing I4 is a circular disk 'ill which serves as a journal upon which the elem-ents' I0 and I8 may be mounted, insuperposedrelation, by fitting the openings I9 and- ZE?" successively over the element 2i. The latter element has a thicknessl approximately equal to the combined thicknesses of the apertured portions of the elements Hl and I8. The disk-shaped element 22, somewhat larger than the element 2i, is then secured to the latter in concentric relationship thereto. `The elements I4, 2f and 22 are thus permanently and im- .movably associated with one another, and may be deemed-to be relatively xed with respectto the relatively' movable elements I0 and I8. Simpleadhesive'means may be employed to hold these fixed elementsl together, ora staple or `other fastening' Linstrumentality may be employed, if desired. The element ISmay be rotatably mountedA on the end of the arm lv in any similar or convenient manner, and I have illustratively shown a construction in which' the element i9 is considin'ably smaller than the element I0' and is pivoted to the element I8 by means of" an eyelet 23("see Figure 2'). v

kOn its top surface, the element 2 carries circumferential' indicia which define a compass rose, asshown most clearly in Figure l. From the foregoing description, it willv be understood that The elements III and I8 being in superposed relation, it may be desirable to make the upper element (in the illustrated form the element I8) of transparent material. 22 may also be of transparent material, and in general, any transparencies or apertures may be provided for, wherever better visibility of underlying parts or markings is facilitated thereby.

On the/element I9 I provide a set of radial markings 26 similar to those on the element I0, these markings including a lubber line (the longitudinal marking which passes through the bow and stern portions of the element I9) and degree numerals or other explanatory markings may be employed if desired'.

While the mode of use of the device is believed,

to have been clearly indicated by the foregoing description, it may be pointed out that the independent rotatability of the several parts, and the conjoint assembly of the parts in the manner shown, permits numerous different relationships to be tested and; studied. For example, the registration of" the lubber line If3A with the circumferential indicia on the compass rose element 22 permits a-study or various compass bearings of the vessel which the element ID' represents. The-sim'- i-lar registration of the line 25 with the compass rose indicia; permitsA a study of" various compass bearings of the target or vessel I9' with respect to the imaginary vessel on which the compass is mounted. Theregistratiorr of'theline' 25 with the various radial markings onthe element Ile permits a study of various relative bearings" of the target with respect to the vessel I-U. And the registration of' the line 25 with the markings 2G on the element I9' permits a stud of various target angles of the vessel I9' relative to the vessel I0.

' In general, it will be' understood that the details herein described and illustrated to explain v the generalv nature of theinventiorr may be modithese markings or indicia are constantly xed,

positionally, with respect to the backing I4. This corresponds to the relatively Xed position which On the element III, in addition to the base line I3, there are radial markings 2"4 arranged at selected different degrees` from the lubber line I3. I' have illustratively shown a series of radial lines' at 30 intervals.. with numerals associated therewith to designate their angular relationships, measured clockwise from the lubber line I3, i. e., frornthe direction of travel or heading of the vessel which the element IG. represents.

The arm element I8 carries indicia which I have shown in the form of a radial line 25, adapted to register with the compass rose indicia and with the markings on the element IU as rotative adjustmentsof the arm I8' are affected relative to the compass rose element 22, and as relative rotativeadjustmentsof the elements ISI-and I a are effected.

ned' by those' skilled in the art without departing from the spiritr and scope of the invention as expressed in the appended claims; It' is therefore intended that these.V details' be interpreted as illustrative and not in a limiting sense.

Having' thus described my invention and illustrated its use', what I claim as new and desire to secure by Letters Patent is:

'1: In a training'aid, a pairI of mutually pivoted elements adapted to beY independently rotated in a plane perpendicular to the pivot axis, one of said elements depicting a vessel in plan view outline andfprovided with a lineal radial' marking deining the lubber line of saidY vessel the other element being an arm extending radially beyond said outline and provided at its end with a representation in plan view ofY a target whereby diiferent relative bearings. may be studied by' rotative adjustments of said arm relative' to said' lub-- ber line said elements being pieces of ilat sheet material arranged' in superposed relation.

2. In a training aid, a pair of mutually pivoted p elements adapted: to. be independently rotated in a plane perpendicular to the pivot axisv one of ber line. of said other vesseL, whereby diierent 'relative bearings and' target angles may' be If desired, the element studied by rotative adjustments of said arm relative to said lubber lines.

3. In a training aid, the structure set forth in claim l, the upper one of said elements being transparent.

4. In a training aid, the structure set forth in claim 1, said first-named element having lineal radial markings at selected different degrees from said lubber line, and said arm having lineal radial indicia adapted to register with said markings as said adjustments are effected.

5. In a training aid, the structureset forth in claim 2, said elements being pieces of'flat sheet material, the vessel elements being arranged in superposed relation to said arm.

6. In a training aid, the structure set forth in claim 2, each of said vessel elements having radial markings at selected different degrees from the corresponding lubber line, and said arm having radial indicia adaptedl to register with said markings as said adjustments are effected.

'7. In a training aid, the structure set forth in claim 2, each of said vessel elements having radial markings at selected different degrees from the corresponding lubber line, and said arm having radial indicia adapted to register with said markings as said adjustments are effected, said elements being pieces of iiat sheet material,

the vessel elements being arranged in superposed ments of said arm and vessel elements relative to each other and to said compass rose.'

9. In a training aid, a relatively fixed element X depicting a compass rose, and a pair of elements concentrically pivoted thereto so as to be independently rotatable in a plane perpendicular to the pivot axis, one of said elements depicting a vessel in plan view and provided with a radial marking defining the lubber line of said vessel, the other element being an arm provided at its end with a representation in plan view of atarget, whereby dilierent compass bearings and relative bearings may be studied by rotative adjustments of said arm and vessel elements relative to each other and to said compass rose, said elements being pieces of flat sheet material arranged in superposedv relation. 1

10. In a. training aid, a flat backing element, a flat element ixed thereon in slightly spaced superposed relation thereto and depicting a compass rose, and a pair of relatively movable flat elements mounted in said space and pivoted. to said backing concentrically with respect to said compass rose so as to beindependently rotatable in their own planes, one of said movable elements depicting a vessel in plan view and provided with a radial marking deiining the lubber line of said vessel, the other movable element being an arm provided at its end with a representation in plan view of a target, whereby different compass bearings and relative bearings may bestudied by rotative adjustments of said arm and Vessel eley ments relative to each other and to said compass rose.

11. In a training aid, the structure set forth in claim 10, said vessel element having radial l markings at selected different degrees from said lubber line, and said arm having radial indicia adapted to register with said markings as well as with said compass roseindiciaas said adjustments are effected.

12. In a training aid, a flat backing element, a iiat element iixed thereon vin slightly spaced superposed relation thereto and depicting a compass rose, and a pair of relatively movable flat elements mounted in said space and pivoted to said backing concentrically with respect to said compass rose so as to be independently rotatable in their own planes, one of said movable elements depicting a vessel in plan view and provided with a radial marking d'ening the lubber line of said vessel, the other movable element being an arm provided at its end withl arepresentation of a target, said target representation comprising a flat element pivoted to said arm and depicting another vessel in plan view, said depiction including a radial marking deiining the lubber line of said other vessel, whereby diiierent compass bearings, relative bearings, and target angles vmay be studied by rotative adjustments of said arm and vessel elements relative to one another and to said compass rose.

13. In a training aid, the structure set forth in claim 12, each of said' vessel elements having radial markings at selected different degrees from the corresponding lubber line, and said arm having radial indicia adapted to register with said markings as Well as with the compass rose indicia as said adjustments are effected.

JOHN V. HORR. 

